At present, various robots have been put into practice in various fields and are in operation. Almost all the robots are based on a teaching and playback system. In order to cause the robots to carry out movements and commands, it is necessary for a robot operator to prepare work programs by teaching work. Various types of movement commands and work commands are described in the work programs. By selecting and carrying out the work programs after the work programs are prepared, a robot executes a series of movements and works per teaching.
The teaching method of a robot, which is disclosed in Japanese Laid-Open Patent Publication No. Hei-8-19975 stores teaching data with identification numbers attached per work section, wherein editing of a sequence of a work section is enabled.
However, in order to modify the position/posture of a robot, movement conditions and work conditions thereof, it is necessary to change the work programs. However, where a series of work programs include several tens through several hundreds of work points, it is difficult to recognize sections where the robot actually operates, by only checking the movement section and work section in the programs written in terms of a robot language.
In this case, in the prior arts, an operator specifies an appointed section by pressing the operation key for respective teaching positions, one by one, many times regardless of whether it is an air-cut section or work section from the top of work programs, or manually guides the robot to an appointed section while paying sufficient attention so that the robot is not made to collide with fixtures, workpieces, and obstacles such as surrounding facilities. Therefore, a great amount of time and labor are required.
As has been disclosed in the above-described Japanese Laid-Open Patent Publication No. Hei-8-19975, in order to cause the robot to move from a certain teaching point to the next teaching point, it was necessary to cause the robot to reach a target work section by operating a key on the operation panel one by one by using a so-called step feeding means. As in the method described in the above-described Japanese Laid-Open Patent Publication No. Hei-8-19975, in the case of painting in which a plane is a work object, the total number of teaching points is comparatively small, and it is comparatively easy to cause the robot to reach the target work section through step feeding by the operation key. However, in the case of welding in which a complicated space is a work object, since there is a section for preventing an object work and a welding torch from being made to interfere with each other, an approaching section to a commencement position of a welding work section, and a section from the terminating section to the welding torch retreating section are indispensable, remarkably more movement sections other than work sections, than in the case of painting are provided, wherein it is necessary for an operator to repeatedly press the operation key many times in order to guide or lead the robot to an object work section by step feeding. With the method disclosed in Japanese Laid-Open Patent Publication No. Hei-8-19975, the problem cannot be solved. Also, since it is necessary to operate the key many times and attention must be paid to avoid obstacles, there arises a danger that may be brought about due to a lack of attention in the movements of the robot.
On the other hand, in a case where a plurality of work programs are prepared, there may be a case where which program corresponds to an appointed work becomes unclear. In such a case, the robot operator selected a work program, read the work program from the beginning to the end, and confirmed it.
As a method for facilitating confirmation of such a work program description, there is a method that is described in Japanese Laid-Open Patent Publication No. Hei-5-265534.
Hereinafter, taking welding work for instance, a brief description is given of the method with reference to FIG. 14. First, an appointed work program is selected from a list screen describing work programs as shown in FIG. 14(a). When the work program is selected, the screen is changed to a work program display screen, which is shown in FIG. 14(b). The work program display screen displays a part of the description of the work programs shown in FIG. 14(d). An apparatus described in the above-described patent publication is featured in that, by moving the cursor 40 on the work program display screen, a description incidental to one command of the work program is picked up by using a convenience key. For example, in the program shown in FIG. 14(b), when welding is commenced, a welding start command ARCON is given, and at the same time, the first welding conditions file (welding current, welding voltage, etc.,) (which is described as FILE (1)) is designated. At this time, by pressing a convenience key (not illustrated) after moving the cursor 40 to the welding start command ARCON, the screen is changed to a work file display screen as shown in FIG. 14(c1). Similarly, in order to display the fifth welding conditions file shown in FIG. 14(c2), it is necessary to press the convenience key after the cursor 40 is moved to the command position shown in FIG. 14(c2). Thus, in Japanese Laid-Open Patent Publication No. Hei-5-265534, only information incidental to one command in the work program is picked up and is displayed.
However, in the prior art method for confirming descriptions of work programs, since the work programs are written in terms of movement commands and work commands, which are inherent to a robot controller, there is a problem in that an unskilled operator who is not acquainted with the meanings of the commands that constitute the work programs does not understand what kind of operation is to be carried out under which conditions and by which program.
Simultaneously, in order to understand a work description in the prior art robot controller, it was indispensable that a work program was selected and displayed, and an operator checked the work program from its beginning to its end, retrieved a work command, and confirmed the work conditions. Therefore, in a large work program consisting of several tens of commands, a great amount of time was required to check the contents of a work. Further, in order to check not only the work conditions but also the locus of a robot, there was no way other than actual operation of the robot.
Also, where results of the operation were obtained by executing a plurality of work programs, it was impossible to easily understand to which program the obtained results of the operation belonged or were related.
In addition thereto, where operation information of the work program was managed or controlled, it was necessary to pick up necessary information from the robot controller and for an operator to prepare and edit the work management information. For example, in order to prepare welding work information as shown in, for example, FIG. 15(b), the operator collected work files as shown in FIG. 14(c1) and other information, and prepared and edited the same.